Re: [PATCH v9 2/2] examples/l3fwd-power: add PM QoS configuration

[fengchengwen <fengchengwen@huawei.com>]

Hi Huisong,

On 2024/8/9 17:50, Huisong Li wrote:
> Add PM QoS configuration to declease the delay after sleep in case of
> entering deeper idle state.
> 
> Signed-off-by: Huisong Li <lihuisong@huawei.com>
> Acked-by: Morten Brørup <mb@smartsharesystems.com>
> ---
>  examples/l3fwd-power/main.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/examples/l3fwd-power/main.c b/examples/l3fwd-power/main.c
> index 2bb6b092c3..9b386c3710 100644
> --- a/examples/l3fwd-power/main.c
> +++ b/examples/l3fwd-power/main.c
> @@ -47,6 +47,7 @@
>  #include <rte_telemetry.h>
>  #include <rte_power_pmd_mgmt.h>
>  #include <rte_power_uncore.h>
> +#include <rte_power_qos.h>
>  
>  #include "perf_core.h"
>  #include "main.h"
> @@ -2260,6 +2261,22 @@ init_power_library(void)
>  			return -1;
>  		}
>  	}
> +
> +	RTE_LCORE_FOREACH(lcore_id) {
> +		/*
> +		 * Set the worker lcore's to have strict latency limit to allow
> +		 * the CPU to enter the shallowest idle state.
> +		 */
> +		ret = rte_power_qos_set_cpu_resume_latency(lcore_id,
> +					RTE_POWER_QOS_STRICT_LATENCY_VALUE);
> +		if (ret < 0) {
> +			RTE_LOG(ERR, L3FWD_POWER,
> +				"Failed to set strict resume latency on CPU%u.\n",

suggest on core%u and use if (ret != 0)

and how about use warning, if current system don't support it, we just give a warning message
but let's it continue.


> +				lcore_id);
> +			return ret;
> +		}
> +	}
> +
>  	return ret;
>  }
>  
> @@ -2299,6 +2316,13 @@ deinit_power_library(void)
>  			}
>  		}
>  	}
> +
> +	RTE_LCORE_FOREACH(lcore_id) {
> +		/* Restore the original value in kernel. */
> +		rte_power_qos_set_cpu_resume_latency(lcore_id,
> +				RTE_POWER_QOS_RESUME_LATENCY_NO_CONSTRAINT);
> +	}
> +
>  	return ret;
>  }
>  
>